Chart 7-1. TROUBLESHOOTING CHART - TM-5-6350-262-14-20034

Chart 7-1. TROUBLESHOOTING CHART

Step

Procedure

Symptom

Corrective measures

Constant alarm condition even

a. If voltage is below tolerance disconnect leads from

a. Check for 20 2 Vdc at

with all GAIN controls (fig.

terminal 7 and 8 of TBl

terminals 7 and 8 of TB1 (fig. 1-1) and measure the

1-1) turned down to 1.

(fig. 1-1) in the processor.

voltage level from the source.

b. If voltage is still below tolerance check inter-

connecting wiring (para 7-7).

c. If voltage is normal replace processor PC board with

a spare and check the processor and receiver (para

2-14).

b . If operating in conjunc-

a. If no SYNC pulse is present refer to TM 5-6350-

tion with a processor/

262-14/14.

transceiver

ultrasonic motion signal,

b. If SYNC pulse is present. replace the processor PC

verify the presence of

board with a spare and reset the receiver GAIN

1 .2V rms SYNC pulse

control (fig. 1-1) and the processor SENSITIVITY

between terminals 7 and

control (fig. 1-1) as outlined in paragraph 2-8.

2 of TB1 (fig. 1-1).

Replace the faulty PC board and repeat procedures

c. Check the tamper

switches (fig. 1-1) as out-

in paragraph 2-14a.

lined in paragraph 2-14 a.

Poor sensitivity at all

a. Check for 5.3 .5Vdc at

a. If voltage is low or zero, disconnect the leads

receivers.

terminals 1 and 2 of TB2

from terminals 1 and 2 of TB2 (fig. 1-1 ) and

(fig. 1-1) in the processor.

check the voltage at the processor terminal

1 and 2 of TB2 (fig. 1-1 ).

b. If the voltage is normal (5.3 .2Vdc) check the

interconnecting wires according to procedures

in paragraph 7-6.

Note: All receiver preamplifier outputs are connected

in parallel. Therefore a multimeter connected to the

leads removed from terminals 1 and 2 of TB2 (re-

ceiver, fig. 1-1) should read a finite resistance for one

polarity, and a resistance approximately 30 times

higher for the opposite polarity. A low resistance ob-

served for both polarities indicates a short in the sys-

tem requiring sequential disconnection of the re-

ceivers to isolate the problem.

c . If the voltage is still low replace the processor PC

board with a spare one and perform procedures

in paragraph 2-8.

Poor sensitivity at one

a . If the voltage is normal at terminal 1 and 2 of TB1

a. Check for 5.3 + .2 Vdc

(fig. 1-1), replace the receiver PC board and perform

receiver.

at terminals 1 and 2 of

the procedures in paragraph 2-8.

TB1 (fig. 1-1) in the

faulty receiver.

b . If the voltage is low, disconnect the leads from

terminals 1 and 2 of TB1 (fig. 1-1) (faulty re-

ceiver) and measure the voltage at the line.

c . If the voltage is normal at the interconnecting

wires, replace the receiver PC board and perform

the procedures in paragraph 2-8.

d . If the voltage is still low, check the interconnect-

ing wires for a short circuit or low resistance

(para 7-6).

Section IV. MAINTENANCE

7-9. Removal and Replacement Proce-

(3) Remove and retain the seven 6-32 x 3/8 inch

long screws fastening the PC board to the enclosure

dures

interior. Remove the PC board.

Processor PC Board Removal (fig. C-1).

b. Processor PC Board Installation (fig. C-1).

(1) Remove and retain the two 6-32 x 3/8 inch

(1) Orient the PC board so that the terminal

long screws fastening the cover to the enclosure.

boards (TB1 and TB2) are adjacent to the conduit

(2) Tag, identify, and remove the leads from

entrance. Secure the PC board to the enclosure using

terminal boards TB1 and TB2.

seven 6-32 x 3/8 inch long screws.

7-4